Stopping structure of fan

ABSTRACT

A stopping structure of a fan is described. An opening is opened on a surface of a frame, and a bearing support is disposed within the frame. A blade wheel is accommodated within the frame and pivoted to the bearing support. Then, a stopper is disposed at the frame corresponding to the opening, such that a distance between the stopper and the blade wheel is smaller than a distance between blades of the blade wheel and the frame. When the blade wheel moves outwards relative to the bearing support, the blade wheel is stopped by the stopper to prevent the blades from interfering with the frame, and a reactive force is generated at an axial center position of the blade wheel, so that an axle of the blade wheel is maintained on the same central axis as the bearing support when the axle restores an original position thereof.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 098211642 filed in Taiwan, R.O.C. on Jun. 26, 2009, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to a stopping structure, and more particularly to a stopping structure of a fan.

2. Related Art

With the rapid development of high technologies, electronic elements such as chips in electronic devices develop towards a miniaturization trend, the intensity per unit area becomes even higher, and the performance thereof is continuously improved. Due to the above factors, the total heat generated by the electronic elements is increased year by year. If there is no desirable heat-dissipation manner for dissipating the heat generated by the electronic elements, the excessive high temperature may shorten the service life of the electronic elements. Therefore, how to dissipate the heat to prevent the electronic elements from becoming too hot has always been a problem beyond negligence.

In order to solve the heat-dissipation problem of electronic elements, a heat-dissipation fan is commonly used to dissipate the heat generated by the electronic elements. For example, in a notebook computer, a heat-dissipation fan is generally disposed on electronic elements (for example, chips, a central processing unit (CPU), or integrated circuits (ICs)) of a motherboard, such that the heat-dissipation fan operates to generate an air flow for exchanging heat, so as to enable the electronic elements to maintain their operational efficiencies within a certain temperature range. Meanwhile, considering the heat-dissipation efficiency of the heat-dissipation fan and the thin design of the notebook computer, a side-blowing blower fan is generally adopted to provide an air flow with a higher pressure, thereby achieving a better heat-dissipation effect.

Such a conventional blower fan mainly comprises a case and a fan accommodated within the case. An air outlet is opened on a side edge of the case. The fan is disposed on a bearing sleeve in the case, and the bearing sleeve has an oil-lubricated bearing therein. The fan is pivoted in the bearing by a rotating shaft. After the rotating shaft is inserted into the bearing, a C-shaped snap ring is snapped at a bottom portion of the bearing sleeve corresponding to one end of the rotating shaft, so as to prevent the fan blades from detaching from the oil-lubricated bearing by using the weight of the C-shaped snap ring.

However, the structural design of the C-shaped snap ring requires an additional space in the bearing sleeve to accommodate the C-shaped snap ring, and as a result, the entire structure of the blower fan cannot be further thinned. What's worse, the C-shaped snap ring is easily worn out or even loosened due to elastic fatigue after the blower fan operates for a long period of time.

Moreover, with the thinning development of structures inside the notebook computer, the height of a blower fan is greatly reduced. Accordingly, a blower fan structure with no C-shaped snap ring was proposed in the prior art. Basically, an air inlet is opened on upper and lower surfaces of a case of the blower fan, and the air is drawn into the case via the air inlet by the rotation of fan blades, and then the air flow is guided to an air outlet and then blown outwards. In order to guide the air flow to flow out of the case via the air outlet, a bearing sleeve and a fan structure are disposed at an eccentric position of the blower fan, in which the eccentric position is not located right at the center of the case. In other words, after the bearing sleeve and the fan are disposed at the eccentric position, one side edge of the fan blade is spaced from the case by a larger distance, the other side edge of the fan blade is spaced from the case by a smaller distance, and a passage for guiding the air flow is formed by using the larger distance.

In order to prevent the fan blades from detaching from the bearing, when the structure of the blower fan is designed, the air inlet is generally designed with such a small aperture that the aperture of the air inlet is smaller than an outer diameter of the fan blades. As such, the fan blades are stopped by the case, so that the rotating shaft of the fan blades is prevented from detaching from the bearing. However, since the fan has a small size and a light weight, if the case itself is used to prevent the rotating shaft of the fan from detaching from the bearing, the fan blades inevitably collide with the case. As the two side edges of the fan blade are spaced from the case by different distances, the arms of force are different when the two side edges of the fan blade collide with the case, and as a result, different reactive forces are exerted on the two side edges of the fan blade. In this case, due to the different reactive forces exerted on the two side edges of the fan blade, the rotating shaft of the fan with excessive light weight easily displaces, shakes, or even gets jammed in the bearing when restoring the original position thereof, such that the rotating shaft cannot be maintained at the same axial center as the bearing. As a result, the rotating shaft interferes with the bearing to cause noises or unsmooth rotation or even cause a failure of the fan, thus greatly reducing the service life of the entire fan.

Therefore, how to solve the above problems and defects is a research direction as for manufactures in the industry.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention is a stopping structure of a fan, so as to solve the problem in the prior art that when the blower fan uses the case itself to prevent the rotating shaft of the fan from detaching from the bearing, the rotating shaft of the fan with excessively light weight easily displaces or shakes when restoring an original position thereof due to different reactive forces exerted on the two side edges of the fan blade, and as a result, the rotating shaft is abraded due to the friction with the bearing or even jammed in the bearing.

A stopping structure of a fan is provided in an embodiment of the present invention, which comprises a frame, a blade wheel, and a stopper. An opening is opened on a surface of the frame, and a bearing support corresponding to the opening is disposed within the frame. The blade wheel is disposed within the frame. The blade wheel comprises a hub and a plurality of blades annularly disposed on the peripheral edge of the hub, and the hub comprises an axle pivoted in the bearing support. Then, the stopper is disposed at the frame corresponding to the opening, such that the stopper is spaced apart from the hub by a first distance, the blades are spaced apart from the frame by a second distance, and the first distance is smaller than the second distance. When the blade wheel moves outwards relative to the bearing support, the hub is stopped by the stopper to prevent the blades from interfering with the frame, and a reactive force is generated at an axial center position of the hub, so that the axle is maintained on the same central axis as the bearing support when the axle restores an original position thereof.

The efficacy of the present invention lies in that, the stopper stops the hub of the blade wheel, so as to prevent the plurality of blades at the peripheral edge of the hub from colliding with the frame during operation. Meanwhile, when stopping the hub, the stopper generates a reactive force at the axial center position of the hub, such that the axle is maintained on the same central axis as the bearing support when the axle restores an original position thereof. As such, the rotational stability and smoothness of the blade wheel are effectively improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus is not limitative of the present invention, and wherein:

FIG. 1 is a schematic view of an external appearance of a stopping structure of a fan according to an embodiment of the present invention;

FIG. 2 is a cross-sectional side view of a stopping structure of a fan according to the embodiment of the present invention;

FIG. 3 is a cross-sectional side view of a stopping structure of a fan in an inverted state according to the embodiment of the present invention; and

FIG. 4 is a cross-sectional side view of a stopping structure of a fan according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In a stopping structure of a fan provided according to the present invention, the fan may be an axial fan or a blower fan applicable to electronic devices requiring heat dissipation such as a display card chipset, a memory module, or a motherboard chipset. In the following embodiments of the present invention, the blower fan is taken as an example. However, the application products and scope of the present invention are not limited to the following embodiments.

FIG. 1 is a schematic view of an external appearance of a stopping structure of a fan according to an embodiment of the present invention. FIG. 2 is a cross-sectional side view of a stopping structure of a fan according to the embodiment of the present invention.

Referring to FIGS. 1 and 2, a stopping structure of a fan in the present invention comprises a frame 10, a blade wheel 20, and a stopper 30. The frame 10 mainly comprises a bottom plate 11, a plurality of side plates 12 erected on the peripheral edge of the bottom plate 11, and a cover plate 13 covered on the side plates 12. The bottom plate 11, the plurality of side plates 12, and the cover plate 13 constitute an accommodating space 14. In addition, a bearing support 15 located within the accommodating space 14 is disposed on the bottom plate 11, and the bearing support 15 and the bottom plate 11 may be integrally formed. A bearing 151 is disposed within the bearing support 15, a coil 152 is wound around the exterior of the bearing support 15, and at least one magnet 153 is disposed corresponding to the coil 152. However, the electromagnetic interaction produced between the coil 152 and the magnet 153 belongs to the prior art, and is not a technical feature of the present invention, so that the structures thereof are not described in detail herein.

Moreover, an air outlet 121 is opened on one of the side plates 12 of the frame 10, and is used for guiding an air flow generated by the rotation of the blade wheel 20 towards the air outlet 121, so that the air flow is blown outwards via the air outlet 121.

In addition, an opening 131 is opened on the cover plate 13, such that a position of the opening 131 is corresponding to that of the bearing support 15.

The blade wheel 20 is accommodated within the accommodating space 14 of the frame 10, and the blade wheel 20 comprises a hub 21 and a plurality of blades 22 annularly disposed on the peripheral edge of the hub 21. The hub 21 comprises an axle 23 therein, such that the axle 23 is correspondingly inserted into the bearing 151 of the bearing support 15. The axle 23 is pivoted to the bearing 151 to form a rotating shaft structure, so as to drive the hub 21 and the plurality of blades 22 to rotate.

The stopper 30 is disposed at the frame 10 corresponding to the opening 131 of the cover plate 13. A plurality of connecting ribs 31 is mainly disposed on a peripheral edge of the stopper 30, and the stopper 30 is connected to an inner wall surface of the opening 131 of the cover plate 13 by the connecting ribs 31. The stopper 30 further comprises a bump 32 protruding from one side surface thereof, such that the protruding position of the bump 32 is corresponding to the hub 21.

It should be particularly noted that, the bump 32 is spaced apart from the hub 21 by a first distance D1, the cover plate 13 is spaced apart from the blades 22 by a second distance D2, and the first distance D1 is smaller than the second distance D2. In other words, when the frame 10 is normally placed, the bearing support 15 is located at the bottom of the frame 10, and the blade wheel 20 is pivoted to the bearing support 15. As such, when the hub 21 rotates, the blades 22 do not collide with the cover plate 13 of the frame 10 during rotation due to the second distance D2 between the cover plate 13 and the blades 22.

FIG. 3 is a cross-sectional side view of a stopping structure of a fan in an inverted state according to the embodiment of the present invention. Referring to FIG. 3, if the frame 10 is inverted, the bearing support 15 is inverted and located above the frame 10, and the blade wheel 20 pivoted to the bearing support 15 is located below the frame 10, such that the axle 23 of the blade wheel 20 may slide out of the bearing 151. At this time, the bump 32 of the stopper 30 stops at an axial center position of the hub 21, so as to maintain the axle 23 on the same central axis as the bearing support 15, thereby preventing the blade wheel 20 from detaching out of the bearing support 15.

Moreover, as the first distance D1 between the bump 32 and the hub 21 is smaller than the second distance D2 between the cover plate 13 and the blades 22, when the frame 10 is inverted, not only the bump 32 stops one side surface of the hub 21 to prevent the blade wheel 20 from detaching from the bearing support 15, but also the blades 22 are prevented from being damaged or interfered to stop rotation due to the collision with the cover plate 13 during rotation.

Therefore, even if the frame 10 is placed in different directions, the bump 32 of the stopper 30 presses against the axial center position of the hub 21 to generate a reactive force, such that the axle 23 is maintained on the same central axis as the bearing support 15 when the axle 23 restores an original position thereof. Furthermore, the blade wheel 20 is stably positioned within the accommodating space 14 of the frame 10, so as to effectively prevent the blades 22 from colliding with the cover plate 13 of the frame 10, thus avoiding any damage or unsmooth rotation of the blades 22.

Accordingly, when the blade wheel 20 rotates, the axle 23 is stably maintained on the central axis of the bearing support 15 by using the structural design of the stopper 30, thereby preventing the axle 23 of the blade wheel 20 from detaching out of the bearing support 15 and preventing the blades 22 from colliding with the frame 10 during rotation. As such, the surrounding air is guided by the stably-rotating blades 22 and is drawn into the accommodating space 14 of the frame 10 via the opening 131, and then blown by the blades 22 towards the air outlet 121 of the frame 10, and then blown outwards via the air outlet 121, so as to dissipate the heat generated by related electronic devices.

FIG. 4 is a cross-sectional side view of a stopping structure of a fan according to another embodiment of the present invention. Referring to FIG. 4, this embodiment is approximately the same as the structure of the above embodiment, so that merely the differences there-between are illustrated below. In the stopping structure of a fan of the present invention, a bump 211 is disposed on one side surface of the hub 21, such that the bump 211 is spaced apart from the stopper 30 by a first distance D1, the blades 22 are spaced apart from the cover plate 13 by a second distance D2, and the first distance D1 is smaller than the second distance D2.

As the first distance D1 between the bump 211 and the stopper 30 is designed to be smaller than the second distance D2 between the blades 22 and the cover plate 13, when the blade wheel 20 moves relative to the bearing support 15, the bump 211 of the hub 21 is stopped by the stopper 30, thereby preventing the blades 22 from being damaged or interfered to stop rotation due to the collision with the cover plate 13 during rotation.

The efficacy of the stopping structure of a fan in the present invention lies in that, the stopper disposed at the opening of the frame is utilized to prevent the blades of the blade wheel from interfering with the frame. Meanwhile, when the hub collides with the stopper, the stopper generates a reactive force at the axial center position of the hub, such that the axle is maintained on the same central axis as the bearing support when the axle restores an original position thereof, thereby enabling the axle to stably and smoothly rotate within the bearing. 

1. A stopping structure of a fan, comprising: a frame, comprising an opening opened on a surface thereof, wherein a bearing support corresponding to the opening is disposed within the frame; a blade wheel, disposed within the frame, wherein the blade wheel comprises a hub and a plurality of blades annularly disposed on a peripheral edge of the hub, and the hub comprises an axle pivoted in the bearing support; and a stopper, disposed at the frame corresponding to the opening, wherein the stopper is spaced apart from the hub by a first distance, the blades are spaced apart from the frame by a second distance, the first distance is smaller than the second distance, and when the blade wheel moves outwards relative to the bearing support, the hub is stopped by the stopper to prevent the blades from interfering with the frame, and a reactive force is generated at an axial center position of the hub, so as to maintain the axle on the same central axis as the bearing support when the axle restores an original position thereof.
 2. The stopping structure of a fan according to claim 1, wherein the stopper further comprises a bump corresponding to the hub, and the first distance is a distance between the bump and the hub.
 3. The stopping structure of a fan according to claim 1, wherein the hub further comprises a bump corresponding to the stopper, and the first distance is a distance between the bump and the stopper.
 4. The stopping structure of a fan according to claim 1, wherein the stopper further comprises at least one connecting rib, and the connecting rib is connected to the opening of the frame.
 5. The stopping structure of a fan according to claim 1, wherein the bearing support further comprises a bearing pivoted to the axle, a coil is disposed around an outer edge of the bearing support, and at least one magnet is disposed corresponding to the coil. 